Asthma Attack: What to Do, Signs to Watch For, and When to Call 999
▶ Asthma attack UK
An asthma attack is a sudden, severe worsening of asthma symptoms caused by airway narrowing, swelling, and excess mucus. Use your reliever inhaler (salbutamol/Ventolin) — 1 puff via spacer every 30–60 seconds, up to 10 puffs. Call 999 immediately if symptoms do not improve after 10 puffs, you cannot speak in full sentences, or lips or nails turn blue.
Think You May Be Having an Asthma Attack?
If you are currently experiencing difficulty breathing, stop reading and use your reliever inhaler now. If symptoms do not improve after 10 puffs, call 999 immediately.
Call 999 if severe — or manage your asthma online →What Is an Asthma Attack?
An asthma attack occurs when the airways become suddenly and severely narrowed, making breathing significantly harder than usual. The airways swell, the muscles around them contract, and excess mucus is produced — all simultaneously. The result is a dramatic reduction in airflow, producing the characteristic wheeze, breathlessness, and chest tightness of an acute episode.
An asthma attack is different from day-to-day asthma symptoms. It is more severe, develops more rapidly, and may not respond to the usual reliever dose. Attacks vary enormously in severity — from mild (resolves in minutes with 1–2 puffs of reliever) to life-threatening (requiring emergency oxygen, nebulisers, and hospital admission).
For a full overview of asthma and its triggers, see: Asthma Explained: Symptoms, Triggers, Causes & Treatment.
Warning Signs of a Worsening Asthma Attack
Recognising the early signs of a worsening attack gives you time to act before the situation becomes critical. Key warning signs include:
- Reliever inhaler becoming less effective — needing it more frequently, or finding it provides less relief than usual
- Waking at night with coughing, wheezing, or breathlessness
- Worsening symptoms that are not settling after 10 puffs of reliever via spacer
- Peak flow dropping below 50% of your personal best (red zone on your asthma action plan)
- Inability to speak in full sentences due to breathlessness
Mild, Moderate and Severe: How to Tell the Difference
| Severity | Features | Action |
|---|---|---|
| Mild | Wheeze and breathlessness; can still talk; reliever inhaler effective; peak flow >75% best | Use reliever inhaler; monitor; contact GP if not resolving within 1 hour |
| Moderate | Increasing breathlessness; speaking in short phrases; reliever partially effective; peak flow 50–75% best | Use reliever (10 puffs via spacer); call GP urgently or attend urgent care; call 999 if no improvement |
| Severe | Cannot complete sentences; very breathless; reliever ineffective; peak flow <50% best | Call 999 immediately. Give reliever every minute while waiting. |
| Life-threatening | Silent chest; cyanosis (blue lips/nails); exhaustion; confusion; peak flow <33% best | 999 emergency — do not delay. |
What to Do During an Asthma Attack: Step-by-Step
- 1
Sit upright
Do not lie down. Sitting upright opens the airways and makes breathing easier. Help the person remain calm.
- 2
Use the reliever inhaler with a spacer
Give 1 puff of salbutamol (Ventolin 100mcg) via spacer every 30–60 seconds, up to 10 puffs. If no spacer is available, use the inhaler alone. Each puff should be followed by 5–10 normal breaths through the spacer.
- 3
Wait 15 minutes
If symptoms improve, the person may be having a mild attack. They should still contact their GP or attend urgent care for review on the same day.
- 4
If no improvement after 10 puffs — call 999
Do not wait. Call 999 and tell them it is an asthma attack. Continue giving 1 puff of reliever every minute while waiting for the ambulance.
- 5
Never leave the person alone
Stay with them until the ambulance arrives. Reassure them. Encourage slow, steady breathing.
Call 999 immediately if: the reliever inhaler has had no effect after 10–15 minutes · the person cannot finish sentences · lips or fingernails are turning blue · they are drowsy, confused, or exhausted · a child stops breathing even briefly. While waiting, give 1 puff of reliever inhaler every minute (up to 10 puffs).
Using Your Inhaler and Spacer During an Attack
A spacer significantly increases the amount of medication reaching the airways compared to inhaler alone. During an attack, using a spacer can make a critical difference. Each puff of salbutamol should be administered separately — one puff, then 5–10 breaths through the spacer, then the next puff if needed. Up to 10 puffs in a single attack episode is safe.
For detailed technique guidance, see: How to Use an Asthma Inhaler Correctly: A Step-by-Step Guide and Understanding and Using Your Ventolin Inhaler.
When to Call 999
Many people with asthma are reluctant to call 999, fearing they are overreacting. The following symptoms are absolute indications for a 999 call — do not wait:
- Reliever inhaler (10 puffs) has had no effect after 15 minutes
- The person cannot speak in full sentences due to breathlessness
- Lips or fingernails are turning blue (cyanosis — indicates dangerously low oxygen)
- The person is drowsy, confused, or losing consciousness
- The chest sounds silent (no wheeze) — indicates the airways may be completely obstructed
- A child stops breathing, even momentarily
Asthma Attack vs Panic Attack: How to Tell
Both asthma attacks and panic attacks cause sudden breathlessness and anxiety, and can be confused with each other. Key distinguishing features:
| Asthma Attack | Panic Attack | |
|---|---|---|
| Sound | Wheeze (whistling on exhale) | Usually silent or noisy gasping |
| Breathing pattern | Slow, laboured exhalation | Fast, shallow hyperventilation |
| Response to reliever inhaler | Usually improves within 5–10 min | No direct effect |
| Other symptoms | Chest tightness, cough | Tingling in fingers/face, dizziness, racing heart |
| Triggers | Allergens, cold air, exercise, infection | Stress, anxiety, no identifiable trigger |
| If unsure | Use reliever inhaler — it will not cause harm if the cause is a panic attack | |
After an Asthma Attack: What Happens Next
After any significant asthma attack — even one that resolved with home treatment — a same-day or next-day review with your GP or asthma nurse is important. The attack indicates that your asthma is not adequately controlled, and your treatment plan may need stepping up. Your prescriber will assess whether your preventer dose needs increasing, your technique is correct, and whether your asthma action plan is up to date.
Reducing Your Risk of Future Attacks
- Take your preventer inhaler every day — even when symptom-free. Daily ICS reduces airway inflammation and significantly decreases attack risk.
- Have a written asthma action plan — people with an action plan are four times less likely to be hospitalised for asthma.
- Annual asthma review — ensures your treatment is appropriate and your technique is correct.
- Identify and avoid triggers — see: Types of Asthma Treatment Explained and Autumn Asthma Triggers.
- Flu and COVID-19 vaccinations — viral infections are the most common trigger for severe attacks.
- Carry your reliever inhaler at all times — and check the dose counter regularly.
Order Your Asthma Reliever Online
GPhC-registered pharmacist independent prescribers · NICE NG245–aligned prescribing · Discreet next-day delivery.
Order Ventolin or Salamol →Frequently Asked Questions
What should I do during an asthma attack?
Use your reliever inhaler (salbutamol/Ventolin) — 1 puff via spacer every 30–60 seconds, up to 10 puffs. Sit upright. Stay calm. If symptoms have not improved after 10 puffs, or if they worsen at any point, call 999 immediately. Do not lie down. While waiting for the ambulance, continue giving 1 puff every minute.
When should I call 999 for an asthma attack?
Call 999 immediately if: your reliever inhaler has had no effect after 10–15 minutes; you are too breathless to complete a sentence; your lips or fingernails are turning blue; you feel drowsy, confused or exhausted; or a child has stopped breathing even briefly. A severe asthma attack is a medical emergency.
How long does an asthma attack last?
A mild attack may resolve within a few minutes with reliever inhaler use. A moderate attack may last 15–60 minutes. Severe attacks require emergency treatment and may last several hours. After any significant attack you should always seek same-day medical review — your treatment plan may need adjusting.
Is an asthma attack the same as a panic attack?
No, but they can be difficult to distinguish because both cause breathlessness and anxiety. Key differences: asthma attacks typically cause wheeze (a whistling sound on breathing out), respond to salbutamol within minutes, may include chest tightness, and are often triggered by allergens or illness. Panic attacks tend to cause hyperventilation (fast shallow breathing), tingling in the fingers, and dizziness without wheeze. If in doubt, use your reliever inhaler — it will not cause harm if the cause is a panic attack.
Can you die from an asthma attack?
Yes — asthma attacks can be fatal, but the majority of asthma deaths in the UK are considered preventable. Around 1,400 people die from asthma each year in the UK. Most deaths occur because the attack was not treated quickly enough or because asthma was not well controlled beforehand. Having a written asthma action plan, taking your preventer inhaler daily, and knowing when to call 999 are the three most important steps in preventing a fatal attack.
What causes a severe asthma attack?
Severe attacks are most commonly triggered by viral respiratory infections (particularly rhinovirus), allergen exposure (house dust mites, pollen, pet dander, Alternaria mould spores), air pollution, cold air, and abrupt stopping of preventer inhaler therapy. Under-use of the preventer inhaler is a major contributing factor — poorly controlled underlying inflammation makes the airways far more reactive to triggers.
References
- NICE. Asthma: diagnosis, monitoring and chronic asthma management (NG245). 2024. nice.org.uk/guidance/ng245
- NHS. Asthma. nhs.uk/conditions/asthma
- Asthma + Lung UK. Asthma facts and statistics. asthma.org.uk
- BTS/SIGN. British Guideline on the Management of Asthma (SIGN 158). 2023. sign.ac.uk
- MHRA. Salbutamol (Ventolin Evohaler) summary of product characteristics. medicines.org.uk/emc
- GPhC. Standards for registered pharmacies. pharmacyregulation.org
Medical disclaimer: This article is for informational purposes only and does not constitute medical advice. Asthma inhalers are prescription-only medicines — a clinical consultation is required before they can be dispensed. If you are experiencing a severe asthma attack, call 999 immediately. Always follow the guidance of your prescriber or asthma nurse. In a medical emergency, call 999.